Capless filler neck assembly for a fuel tank

ABSTRACT

A capless seal door for a fuel tank filler tube employs a door valve with a flexible annular seal which, upon closing against a seat on the undersurface of a nozzle-receiving orifice formed in a bulkhead across the tube, initially wipes on the seat and is subsequently compressed thereon.

BACKGROUND OF THE INVENTION

The present invention relates to filler tube assemblies for fuel tanksand particularly fuel tanks employed on passenger car and light truckvehicles. Such fuel tanks and fuel systems for motor vehicles haverecently become subject to mandated requirements limiting fuel vaporemissions into the atmosphere. In addition, it has more recently beenrequired to provide a vehicle on-board diagnostic system to detectleakage of fuel vapors from the tank and fuel system during periods ofengine inoperation. The on-board diagnostics (OBDII) requires a slightvacuum or positive pressurization within the tank to conduct the leaktest; and, therefore, the entire fuel system including the tank fillertube or neck must be capable of being tightly sealed.

The requirement that the fuel system including the tank and the fillerneck be tightly sealed to prevent vapor emission to the atmosphere andenable diagnostic testing with a slight pressure difference fromatmospheric in the tank has resulted in problems in manufacturing thefuel tank and filler, inasmuch as the filler tube cap has been found tobe a source of leakage when improperly replaced or insufficientlytightened after refueling. Thus, it has been desired to provide a way ormeans of eliminating the filler tube cap on motor vehicle fuel tanksystems and yet provide for refueling with a conventional dispensingnozzle and to provide closure upon the nozzle removal in a manner thatensures vapor tight sealing.

Heretofore, proposals for capless filler tubes for motor vehicle fueltanks have been complicated, bulky, difficult to manufacture andassemble in the vehicle and consequently relatively high in cost. Thus,it has long been desired to provide a simple relatively low cost andeasy to manufacture and assemble a capless closure and filler tube for amotor vehicle fuel tank which provides adequate vapor-tight sealingafter refueling.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a one-way door type valve for sealing arefueling nozzle-receiving orifice in a bulkhead at the upper end of amotor vehicle fuel tank filler tube which accommodates a standard fueldispensing nozzle and provides for vapor tight sealing upon removal ofthe nozzle. The capless filler tube fill valve of the present inventionemploys a unique flexible annular seal attached to the door valve whichis biased into contact with a tapered seating surface provided about thenozzle-receiving aperture in the bulkhead and, the door valve is biasedtoward the seating surface in a manner which effects a wiping seal asthe door closes and compression of the seal against a seating surfacearound the nozzle orifice on the downstream side of the bulkhead. Avacuum relief valve is provided in the door valve to permit make up airto enter the tank or due to diurnal temperature changes when the tankvacuum exceeds a predetermined level.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross section of the upper end of a filler tube for a fueltank employing an exemplary embodiment of the present invention;

FIG. 2 is an enlarged view of a portion of the cross section of FIG. 1;

FIG. 3 is an exploded view of the door valve and seal of the embodimentof FIG. 1;

FIG. 4 is a view similar to FIG. 2 of an alternate embodiment of theinvention;

FIG. 5 is a view similar to FIG. 2 of another embodiment of theinvention;

FIG. 6 is a view similar to FIG. 2 showing an additional embodiment ofthe invention; and

FIG. 7 is a view similar to FIG. 2 showing yet another embodiment of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 through 3, a fuel tank filler neck or tube upperend with an exemplary embodiment of the present invention is indicatedgenerally at 10 and has an enlarged diameter portion 12 of the tube 10fitted with a transverse bulkhead 14 at the end thereof. Bulkhead 14 hasformed therein a nozzle-receiving aperture 16 which has formedthereabout on the inner or downstream side of the bulkhead 14 an annularvalve seating surface 18. If desired, the valve seating surface 18 mayhave a spherical configuration as illustrated in FIG. 2.

A door valve 20 is disposed on the downstream side of bulkhead 14 overaperture 16 and has a radially outwardly extending annular flange 22about the periphery thereof which flange has a plurality of apertures 24formed therein and disposed in spaced arrangement circumferentiallythereabout. Door valve 20 also includes a pair of spaced generallyparallel flanges 26, 28 formed on opposite sides thereof for attachmentto a pivoting mechanism (not shown) provided in the tube portion 12.

Upon insertion of the end of a refueling nozzle through aperture, 16 inthe bulkhead, the door is moveable from the closed position shown insolid outline in FIG. 1 to the intermediate position and the fullyopened position shown in dashed outline in FIG. 1. A spring 30 isprovided within the portion 12 of the filler tube and is operative tobias the door valve 20 in a direction toward the closed position.

Referring to FIGS. 1 and 2, an annular flexible seal 32 is formed on theflange 22 of the door valve 20 such as by insert molding, wherein duringthe molding operation the material for the seal flows through theapertures 24 and forms a bead rim 34 on the downstream side of the doorvalve which retains the seal 32 onto the flange 22. The outer peripheryof the seal 32 is sized and configured, as denoted by reference numeral36, to wipe against the valve seating surface, such as spherical surface18, as the door approaches the fully closed position. In the fullyclosed position the surface 36 is compressed between the door valve 20and the surface 18 to ensure a vapor tight seal. As the door approachesthe fully closed position, it will be seen that the seating surface 18and the door valve 20 effect a wedging or camming action of the surface36 against the seat 18. In the present practice of the invention, theseal 32 may be formed of elastomeric material.

Referring to FIGS. 1 and 3, the door valve 20 includes a vacuum reliefvalve indicated generally at 40 which includes an air inlet orifice 42formed centrally in the door valve 20. Valve 40 includes a resilientflexible pad or wafer which may have formed integrally therewith agrommet 46 which is received through orifice 42 and has an outer flangethereof extending over the upward end of the aperture 42. In theembodiment of FIG. 1 the flexible resilient wafer valve 46 has anannular rib 48 disposed thereabout on the downstream side adjacent theouter periphery.

A moveable valve member 50 is disposed against the under surface ofwafer 46 and contacts the surface of rib 48 under the urging of a spring52 which is retained in a recess 54 formed in a retaining plate 56 whichis secured to the inner periphery of door valve 20 by any considerableexpedient as, for example, weldment.

A layer of filter material 58 is disposed over the upper end of grommet44 and is retained by cap 60 which may have at least one peripheralcutout 62 formed in the rim thereof for air flow therethrough. Valvemember 50 has a plurality of recesses 51 formed about the peripherythereof to permit airflow and keep valve member 50 on center in the doorthereby when valve member 50 is pulled downwardly and has moved awayfrom contact with the rib 48 by differential pressure forces resultingfrom sub-atmospheric pressure in the tank acting thereon.

Referring to FIG. 4, another embodiment of the invention is indicatedgenerally at 100 in which nozzle-receiving orifice 102 formed in fillertube bulkhead 104 has a valve seating surface 106 formed on thedownstream side of the bulkhead which surface 106 has in the embodiment100 a conically tapered configuration.

A door valve 108 is disposed adjacent aperture 102; and door valve 108has an annular recess or groove 110 formed in the outer peripherythereof and having received therein a portion of a seal 112.

The flexible annular seal indicated generally at 112 has a relativelythin web portion 114 with a wiper surface 116 formed on the outerperiphery thereof and a bead rim 118 formed on the inner peripherythereof. The bead rim 118 is mechanically inserted into the recess orgroove 110 by stretching the seal 114 over the outer periphery of thedoor valve 108.

As the door valve 206 moves toward the closed position, surface 116makes wiping contact with seating surface 106; and, as door valve 108closes, a tapered surface 120 provided on the door valve compresses thesurface 116 against seating surface 106 as shown in FIG. 4.

Referring to FIG. 5, another embodiment of the invention indicatedgenerally at 200 has a bulkhead 201 provided in the upper end of afiller tube with a nozzle-receiving orifice 202 formed therein. Theundersurface or downstream side of bulkhead 201 has formed thereon agenerally straight cylindrical valve seating surface 204.

Door valve 206 is disposed for closing the aperture 202; and, the doorvalve 206 has an annular recess or groove 208 formed in the outerperiphery thereof. A bead rim portion 210 is formed on the innerperiphery of a flexible annular seal indicated generally at 212. Seal212 may have a relatively thin web portion 214 extending outwardly fromthe bead rim 210 which web 214 has an annular rib 216 formed about theouter periphery thereof. The web 214 rests against an annular taperedsurface 218 provided about the edge of the groove. 208 formed in theouter periphery of the door.

As the door valve 206 approaches the closed position shown in FIG. 5,the outer edge 220 of rib 216 engages seating surface 204 initially inflexible wiping engagement; and, upon further closing rib 216 issubsequently compressed thereon between the seating surface 204 andtapered surface 218. The wiping action serves to ensure clearing offoreign matter and the compression ensures a positive seal.

Referring to FIG. 6, another embodiment of the invention is indicatedgenerally at 300 and employs a nozzle-receiving aperture 302 formed in afuel tank filler tube bulkhead 304 which has extendingly downwardlytherefrom on the underside thereof an annular tapered valve seatingsurface 306 suitable for sealing thereagainst.

The tapered valve seating surface 306 of the embodiment of FIG. 6 has amore rapid or generally wider angle of taper than that of an embodimentof FIG. 4 for purposes as will hereinafter be described.

A door valve 308 is disposed on the underside of bulkhead 302 forclosing aperture 302. Door valve 308 as an annular recess 310 formed inthe outer periphery thereof and has a two-staged tapering surface 312extending outwardly therefrom at a relatively steep angle of taper andwhich transitions to a lesser rate of taper to form surface 314 whichextends to the outer periphery of door valve 308 at a diameter 316 whichis larger than the diameter of orifice 302.

A flexible annular seal indicated generally at 318 has a compound taperformed thereon to conform to surfaces 312 and 314. Seal 318 has anannular bead 320 formed on the inner periphery thereof which it will beunderstood is stretched over door 308 and mechanically inserted intogroove 310. The compound tapered web portion 322 of the seal 318 has anannular rib 324 formed on the outer periphery.

As door valve 308 closes, rib 324 engages the tapered seating surface306 initially in a wiping contact and upon further closing is compressedbetween surfaces 314 and surface 306 as the door 308 is moved to theclosed position shown in FIG. 6.

Referring to FIG. 7, another embodiment of the invention is indicatedgenerally at 400 having a filler tube bulkhead 402 with anozzle-receiving orifice 404 formed therein. The downstream or undersideof bulkhead 402 may have formed thereon an annular seating surface 406having a generally spherical configuration.

A door valve 408 is disposed adjacent on the downstream side andpositioned for closing aperture 404; and, door valve 408 has a lowerportion of the outer periphery denoted 410 as extending to a diametergreater than that of the aperture 404. Door 408 has an annular groove412 formed in the outer periphery which communicates with a taperedsurface 414 extending to the outer periphery. Surface 414 has disposedthereon a backing ring 416 which may have the outer surface thereofformed with a spherical curvature.

A flexible annular seal indicated generally at 418 has a relatively thinweb portion 420 with an annular bead rim 422 formed on the innerperiphery thereof and which is stretched over the periphery of the doorvalve 408 and is mechanically lodged in the annular recess 412. Theouter periphery of the web 420 has formed thereon a bead rim 424 whichfunctions, as the door 408 is moved to the closed position shown in FIG.7, to cause rib 424 to initially wipe against sealing surface 406 andthen to be compressed between surfaces 406 and 416 as the door reachesthe closed position.

The present invention thus provides a unique and novel door valve forthe upper end of a fuel tank filler tube which does not require aclosure cap. The filler tube door valve of the present invention employsan annular flexible seal disposed on the door which upon closinginitially undergoes a wiping action and then compression against atapered seating surface provided about a nozzle-receiving aperture in abulkhead at the upper end of the filler tube. The present invention thusprovides a positive vapor tight seal for a fuel tank filler tube withoutthe need for a closure cap and does so in a manner which is relativelylow in manufacturing costs, is easy to assemble and minimizes the spacerequired for the capless seal.

Although the invention has hereinabove been described with respect tothe illustrated embodiments, it will be understood that the invention iscapable of modification and variation and is limited only by thefollowing claims.

1. A capless filler assembly for a fuel tank comprising: (a) a tubularmember defining a fuel flow path with a refueling nozzle-receiving endand a fuel discharging end adapted for connection to a fuel tank; (b) abulkhead disposed across said nozzle-receiving end with a nozzle guidingaperture therein; (c) a valve seating surface disposed in the flow pathon the downstream side of said bulkhead; (d) a valve member disposedadjacent said seating surface for movement with respect thereto uponinsertion of a nozzle through said aperture, the valve member havingthereon an annular flexible seal operable for contacting said seatingsurface in a wiping motion upon removal of the nozzle from the aperture;and, (e) structure operative to bias said valve member in a directionfor effecting said wiping motion and for effecting compression of saidseal on said seating surface for blocking the flow path.
 2. The assemblydefined in claim 1, wherein said annular seal includes a relatively thinweb portion having an outer peripheral bead portion.
 3. The assemblydefined in claim 2, wherein said web portion has a conically taperedconfiguration.
 4. The assembly defined in claim 1, wherein said annularseal includes a relatively thin web portion and an inner peripheral beadportion engaging said valve member.
 5. The assembly defined in claim 1,wherein said valve member is mounted for pivotal movement.
 6. Theassembly defined in claim 1, wherein said valve seating surface includesportions having a spherical curvature.
 7. The assembly defined in claim1, wherein said valve member includes an outwardly extending peripheralflange having a plurality of apertures and said annular seal has firstportions disposed on opposite sides of said flange, with second portionsextending through said apertures and interconnecting said firstportions.
 8. A method of making a capless filler assembly for a fueltank comprising: (a) providing a tubular member defining a fuel flowpath with a refueling nozzle-receiving end and a fuel discharging endadapted for connection to the tank; (b) disposing a bulkhead with anozzle guiding aperture in said nozzle-receiving end; (c) disposing avalve seating surface in the flow path on the downstream side of saidbulkhead; (d) disposing a valve member adjacent said seating surface formovement with respect thereto and disposing an annular flexible sealthereon; and, (e) biasing said member in a direction toward said seatingsurface and effecting a wiping motion and compression of said seal onsaid seating surface and blocking the flow path.
 9. The method definedin claim 8, wherein said step of disposing a seal includes forming aseal with a relatively thin web portion having an outer peripheral beadportion.
 10. The method defined in claim 8, wherein said step ofdisposing a seal includes forming a seal having a relatively thin webportion having an inner peripheral bead portion.
 11. The method definedin claim 101, wherein said step of disposing a seal includes attachingsaid bead portion to said valve member.
 12. The method defined in claim8, wherein said step of disposing a valve seating surface includesforming a conically tapered surface.
 13. The method defined in claim 8,wherein said step of disposing a valve member includes disposing avacuum relief valve on the valve member and biasing the vacuum reliefvalve in contact with a second flexible seal and effecting saidcompression.
 14. The method defined in claim 8, wherein said step ofdisposing an annular flexible seal includes forming a plurality ofapertures about the periphery of said valve member and molding sealmaterial therethrough and interconnecting portions of the seal onopposite sides of said valve member.
 15. A capless filler assembly for afuel tank comprising: (a) a tubular member defining a fuel flow pathwith a refueling nozzle-receiving end and a fuel discharging end adaptedfor connection to a fuel tank; (b) a bulkhead disposed at saidnozzle-receiving end with a nozzle guiding aperture therein; (c) aone-way valve disposed in the flow path on the downstream side of thebulkhead with a valve seating surface and a valve member biasedthereagainst for blocking the flow path, the valve operable to be openedupon insertion of a nozzle in said aperture, wherein said valve memberincludes an annular flexible seal operable upon withdrawal of the nozzleto effect sequentially a wiping motion and including structure operableto effect compression of said seal on said seating surface.
 16. Theassembly defined in claim 15, wherein said valve member includes a doordisposed for pivotal movement.